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81.
Koffler Christoph Amor Ben Carbajales-Dale Michael Cascio Joseph Conroy Alison Fava James A. Gaudreault Caroline Gloria Thomas Hensler Connie Horvath Arpad Humbert Sebastien Manzardo Alessandro Margni Manuele Osset Philippe Sinistore Julie Vigon Bruce Wallace Michele L Wang Michael Prox Martina 《The International Journal of Life Cycle Assessment》2020,25(3):478-482
The International Journal of Life Cycle Assessment - 相似文献
82.
Caroline Birer Corrie S. Moreau Niklas Tysklind Lucie Zinger Christophe Duplais 《Molecular ecology》2020,29(7):1372-1385
Bacteria living on the cuticle of ants are generally studied for their protective role against pathogens, especially in the clade of fungus‐growing ants. However, little is known regarding the diversity of cuticular bacteria in other ant host species, as well as the mechanisms leading to the composition of these communities. Here, we used 16S rRNA gene amplicon sequencing to study the influence of host species, species interactions and the pool of bacteria from the environment on the assembly of cuticular bacterial communities on two phylogenetically distant Amazonian ant species that frequently nest together inside the roots system of epiphytic plants, Camponotus femoratus and Crematogaster levior. Our results show that (a) the vast majority of the bacterial community on the cuticle is shared with the nest, suggesting that most bacteria on the cuticle are acquired through environmental acquisition, (b) 5.2% and 2.0% of operational taxonomic units (OTUs) are respectively specific to Ca. femoratus and Cr. levior, probably representing their respective core cuticular bacterial community, and (c) 3.6% of OTUs are shared between the two ant species. Additionally, mass spectrometry metabolomics analysis of metabolites on the cuticle of ants, which excludes the detection of cuticular hydrocarbons produced by the host, were conducted to evaluate correlations among bacterial OTUs and m/z ion mass. Although some positive and negative correlations are found, the cuticular chemical composition was weakly species‐specific, suggesting that cuticular bacterial communities are prominently environmentally acquired. Overall, our results suggest the environment is the dominant source of bacteria found on the cuticle of ants. 相似文献
83.
Caroline R. Cummings Sonia M. Hernandez Maureen Murray Taylor Ellison Henry C. Adams Robert E. Cooper Shannon Curry Kristen J. Navara 《Ecology and evolution》2020,10(15):8416-8428
When wildlife forage and/or live in urban habitats, they often experience a shift in resource availability and dietary quality. Some species even use human handouts, such as bread, as well as human refuse, as a large part of their new diets; yet the influences of this nutritional shift on health and survival remain unclear. American white ibises are increasingly being seen in urban areas in Florida; they collect handouts, such as bread and other food items, from humans in parks, and are also found foraging on anthropogenic sources in trash heaps. We hypothesized that the consumption of these new anthropogenic food sources may trigger increases in indicators of physiological challenge and dampen immune responses. We tested this experimentally by raising 20 white ibis nestlings in captivity, and exposing 10 to a simulated anthropogenic diet (including the addition of white bread and a reduction in seafood content) while maintaining 10 on a diet similar to what ibises consume in more natural environments. We then tested two indicators of physiological challenge (corticosterone and heat shock protein 70), assessed innate immunity in these birds via bactericidal assays and an in vitro carbon clearance assay, and adaptive immunity using a phytohemagglutinin skin test. The anthropogenic diet depressed the development of the ability to kill Salmonella paratyphi in culture. Our results suggest that consuming an anthropogenic diet may be detrimental in terms of the ability to battle a pathogenic bacterial species, but there was little effect on indicators of physiological challenge and other immunological measures. 相似文献
84.
Aline Planchon Gaëlle Durambur Jean‐Baptiste Besnier Carole Plasson Bruno Gügi Sophie Bernard Annabelle Mrieau Jean‐Paul Trouv Caroline Dubois Karine Laval Azeddine Driouich Jean‐Claude Mollet Richard Gattin 《Plant, cell & environment》2021,44(1):304-322
In Normandy, flax is a plant of important economic interest because of its fibres. Fusarium oxysporum, a telluric fungus, is responsible for the major losses in crop yield and fibre quality. Several methods are currently used to limit the use of phytochemicals on crops. One of them is the use of plant growth promoting rhizobacteria (PGPR) occurring naturally in the rhizosphere. PGPR are known to act as local antagonists to soil‐borne pathogens and to enhance plant resistance by eliciting the induced systemic resistance (ISR). In this study, we first investigated the cell wall modifications occurring in roots and stems after inoculation with the fungus in two flax varieties. First, we showed that both varieties displayed different cell wall organization and that rapid modifications occurred in roots and stems after inoculation. Then, we demonstrated the efficiency of a Bacillus subtilis strain to limit Fusarium wilt on both varieties with a better efficiency for one of them. Finally, thermo‐gravimetry was used to highlight that B. subtilis induced modifications of the stem properties, supporting a reinforcement of the cell walls. Our findings suggest that the efficiency and the mode of action of the PGPR B. subtilis is likely to be flax variety dependent. 相似文献
85.
Kopruszinski Caroline M. Swiokla Juliana Lee Yeon Sun Navratilova Edita VanderVeen Laurie Yang Miao Liu Yi Miyazaki Takahiro Schmidt William K. Zalevsky Jonathan Porreca Frank 《Cellular and molecular neurobiology》2021,41(5):949-960
Cellular and Molecular Neurobiology - Pharmacological evaluation of the mu-opioid receptor (MOR) agonist properties of NKTR-181 in rodent models. Graded noxious stimulus intensities were used in... 相似文献
86.
Nir Hecht Caroline L Monteil Guy Perrire Marina Vishkautzan Eyal Gur 《Molecular biology and evolution》2021,38(3):761
The understanding of how proteins evolve to perform novel functions has long been sought by biologists. In this regard, two homologous bacterial enzymes, PafA and Dop, pose an insightful case study, as both rely on similar mechanistic properties, yet catalyze different reactions. PafA conjugates a small protein tag to target proteins, whereas Dop removes the tag by hydrolysis. Given that both enzymes present a similar fold and high sequence similarity, we sought to identify the differences in the amino acid sequence and folding responsible for each distinct activity. We tackled this question using analysis of sequence–function relationships, and identified a set of uniquely conserved residues in each enzyme. Reciprocal mutagenesis of the hydrolase, Dop, completely abolished the native activity, at the same time yielding a catalytically active ligase. Based on the available Dop and PafA crystal structures, this change of activity required a conformational change of a critical loop at the vicinity of the active site. We identified the conserved positions essential for stabilization of the alternative loop conformation, and tracked alternative mutational pathways that lead to a change in activity. Remarkably, all these pathways were combined in the evolution of PafA and Dop, despite their redundant effect on activity. Overall, we identified the residues and structural elements in PafA and Dop responsible for their activity differences. This analysis delineated, in molecular terms, the changes required for the emergence of a new catalytic function from a preexisting one. 相似文献
87.
88.
89.
Kim Tallaksen Halvorsen Torkel Larsen Howard I. Browman Caroline Durif Nicolai Aasen Leif Asbjørn Vøllestad Alessandro Cresci Tonje Knutsen Sørdalen Reidun M. Bjelland Anne Berit Skiftesvik 《Journal of fish biology》2021,99(4):1513-1518
The movement patterns of three commercially important wrasse (Labridae) species inside a small marine protected area (~ 0.15 km2) on the west coast of Norway were analysed over a period of 21 months. The mean distance between capture and recapture locations varied between 10 and 187 m, and was species and season specific. The extent of movement was not related to body size or sex. These results imply that a network of small strategically located marine protected areas can be used as management tools to protect wrasses from size- and sex-selective fishing mortality. 相似文献
90.
Dorette Vermeulen Christopher Klopper Caroline van Niekerk 《Arts Education Policy Review》2013,114(4):199-205
In light of the tendency to present the arts in an integrated fashion in many education systems worldwide, this article examines the consequences of integration for discrete art forms. In particular, we investigate the advantages of adopting a syntegrated approach to the facilitation of arts in teacher preparation. A specific comparison between the implementation of arts curricula in South Africa and Australia is made. The disjuncture between policy and practice in arts education that has been reported internationally needs constant monitoring. We conclude that the heart of curriculum transfer and transformation lies in the classroom. 相似文献